The present invention relates to an apparatus and method of measuring the acceleration of an engine and especially to a method of measuring acceleration of an engine under selected loads to simulate a racetrack's length.
This invention relates to an apparatus and method for measuring acceleration that is particularly suitable for testing race car engines and matching the engine to the car for a particular racetrack and the engine can be used to measure elapsed time at preselected RPMs under selected loads to simulate racetrack lengths. Normally, engines are tested on dynamometers by mounting the engine on a test stand and running the engine so as to measure the output shaft power or torque under controlled conditions. The dynamometer provides a means of absorbing the energy developed by the prime mover and for measuring the output energy. Instruments are connected to different portions of the engine in order to supply information with respect to temperature of different parts, pressures in the intake manifold or combustion chambers of an internal combustion engine, back pressure at the exhaust and the like. Dynamometers are costly and delicate devices which must be maintained in good operating condition for proper operation and interpretation of test data.
Prior U.S. Patents can be seen in the Roberts U.S. Pat. No. 2,362,308, for an Apparatus for Testing Prime Movers which connects a prime mover to a shaft which can have the rear end loaded with weights hanging from the shaft on a radial arm. The Lucia U.S. Pat. No. 3,505,863, is a Method and Apparatus for Testing the Acceleration of Prime Movers in which the output shaft is coupled to a flywheel of known inertia which is driven and accelerated from a first predetermined angular velocity to a second predetermined velocity. The time taken for accelerating the flywheel is measured and the average torque developed by the prime mover is derived from the time taken to accelerate the flywheel. The invention includes a test stand in which the prime mover may be tested while a second prime mover is being installed or connected and for comparing the torque developed by a prime mover to the torque of a reference prime mover.
The Kay et al. U.S. Pat. No. 4,691,288, is a Torque Sensor for Internal-Combustion Engines. A method and apparatus for providing a signal representative of the output torque of an internal combustion engine utilizes a correlation of average engine speed and variations in instantaneous sub-cyclic engine speed. The R. R. De Zurik U.S. Pat. No. 3,285,057, is an Apparatus for Obtaining Torque Measurements, such as a torsional forces applied to a constantly rotating shaft. The Shmuter et al. U.S. Pat. No. 4,758,967, is a Computer Simulated Inertia for Motor Vehicle Powertrain Testing and includes an output motor driven shaft having an inertia disc mounted thereto in an output motor in order to simulate normal driving conditions in a test stand.